主语一致是一方面,Not only还不能在句首.
Not only is she our teacher,but also our friend.主语一致但是not在句首要倒装.
不在句首时不用,如I not only heard it,but also saw it.谢谢，Not only is she our teacher, but also（is） our friend。这里是否需要加is?还有这句话也是两个分句的主语是一致的，那就是可以换成正常语序she not only is our teacher, but also is our friend.不加is，前句中is she直接用于后句，不要重复。正常语序是she is not only our teacher, but also our friend.is前后一致，不要重复。